In recent years, information on the state of the brain is becoming obtainable by nuclear medicine scan such as SPECT (Single Photon Emission Computed Tomography) and PET (Positron Emission Tomography), CT (Computerized Tomography) and MRI (Magnetic Resonance Imaging).
In particular, for the shrinkage of brain tissue, the presence or non-presence of abnormalities can be distinguished by obtaining the volume of particular sites from MRI images and comparing its relative size. For example, according to Patent Document 1, a system for diagnosis support of Alzheimer dementia is disclosed, which provides diagnosis support of Alzheimer dementia by quantitatively evaluating the shrinkage of the middle temporal region using MRI image.